Just some speculative thoughts...I think America will go down several possible paths or perhaps combinations of such....
The rapture occurs and some 150 million plus Americans including a bunch of surprised godly Catholics just disappear leaving the country in a state of collapse as myriads of key people needed to run things are suddenly gone...henceforth the disappearance of America as a superpower....or America is mentioned as part of the seven utterances that the Apostle John(in the book of Revelation) is not allowed to record.
Or...our country collapses into several balkanized states or semi autonoumous regions that the rest of the world, so steeped in their own troubles, doesn’t even bother itself with, perhaps because of economic collapse or limited nuclear exchanges as a result of the Exekiel 37-38 scenarios. Certain regions that produce oil, gas or coal may fare better as some of the remaining world powers will have need of those resources( and Russia will also be so wounded from the Ezekiel scenarios that her ability to supply oil resources will be negatively impacted.) Some where in these timelines the rapture may occur, further weakening the American states.
Or America is mentioned obliquely in prophecy in ways that patriotic Americans would be horrified to realize and come to grips with; to watch as America with its unique abilities in the air, space, and sea becomes the lynchpin state of a dark empire that enslaves the world with the Antichristian BEAST system finally taking power via the American state in the final 7 years of the “times of the gentiles”.
Or America becomes despotic, in need of cash and resources, and it undergoes a series of empire building wars, annexing Canada and Mexico while becoming brutally tyrannical towards all of its citizenry. It becomes one of 10 economic zones finally ruled by the coming Beast system or perhaps becomes the power base of the “little horn” that rules the 10 horns.